Is Urine dipstick as accurate as 24 hour urine protein? A Comparative Study

Abstract

Introduction: Hypertensive disorder in pregnancy (HDP) is one of the most common medical complications affecting approximately 5-10% of pregnancies. It remains a major cause of maternal/perinatal mortality and morbidity. Proteinuria is a sign of preeclampsia where there is >300 mg of protein in 24 hour urine collection. This usually correlates with 30mg/dl or 1+ reading in a random urine specimen. The main objective of this study is to find out whether urine dipstick correlates with 24 hour urine protein.
 Methodology: This is a hospital based comparative study, where proteinuria by dipstick method was compared with 24 hour urinary protein in 60 cases of pre eclampsia at Paropakar Maternity and Women’s Hospital, Thapathali, Kathmandu.
 Results: The dipstick method of detecting proteinuria significantly correlated with the total 24 hour urine protein excretion by Esbach Albuminometer. A dipstick factor of ≥300mg/24 hour indicates proteinuria with sensitivity of 97.5%, specificity of 65%, positive predictive value of 84.78% and negative predictive value of 92.85%. 3+ value in dipstick had high significance with 24 hour urine protein by Esbach’s Albuminometer (R=0.983 ). The cost of dipstick was Nepalies Rs (NPR) 14 in comparison to 24 hour dipstick which cost NPR 80.Time needed to get report was immediate in case of dipstick but takes 48-50 hour in case of 24 hour urine protein.
 Conclusion: Timely collection of six hourly urine for detection of proteinuria by dipstick is comparable to 24 hour urinary protein determination in laboratory by Esbach Albuminometer, which is more time consuming and expensive.

A comparison of spot urinary protein-creatinine ratio with 24-hour urine protein in quantification of proteinuria in women with hypertensive disorders of pregnancy

“…The samples were analysed for the following: 1) Measurement of 24hour urine protein was done by Esbach's method wherein an aliquot is taken from 24hour urinary sample and the reagent (10gm picric acid and 20gm citric acid to 1L distilled water) is added to it. 5,6 Compound is left standing for 24hours then. Precipitated protein is interpreted in gm/litre, 2) Urine creatinine was detected by modified Jaffe's kinetic method, 3) The urine protein and creatinine ratio was obtained by dividing the urine protein concentration (mg/dl) by the urine creatinine concentration (mg/dl).…”